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Creatinine Test

⚠️ Update approaching🔬 Evidence: ModerateInternal Medicine
Diğer adları: Cr, Creatinine level, Serum creatinine
⚠️

Discuss your test results with your doctor. This page is for informational purposes only and does not provide a diagnosis.

⚡ Key Facts

• A byproduct of muscle metabolism, filtered and excreted by the kidneys • Blood levels serve as an indirect indicator of kidney function • Affected by muscle mass, age, sex, and diet • Used as the primary input for eGFR calculation

🧪 What Does This Test Measure?

The creatinine test measures a byproduct of muscle metabolism that is filtered by the kidneys, serving as an indirect indicator of kidney function.

📋 Why Is It Ordered?

Ordered for kidney function evaluation, as the primary input for eGFR calculation, in acute kidney injury detection, chronic kidney disease monitoring, and medication dose adjustment.

🔧 Preparation

Creatinine testing generally requires no special preparation. However, heavy meat consumption or intense exercise before testing may temporarily elevate levels.

📊 Reference Ranges

Commonly used reference ranges: Male: 0.7–1.2 mg/dL (62–106 µmol/L) Female: 0.5–1.0 mg/dL (44–88 µmol/L) ⚠️ Reference ranges vary by laboratory and should be interpreted alongside eGFR.

⬆️ High Values

Elevated creatinine may be associated with decreased kidney function, dehydration, high muscle mass, heavy meat consumption, creatine supplements, or certain medications.

⬇️ Low Values

Low creatinine is generally not a clinical concern. However, it may be associated with low muscle mass (aging, cachexia, neuromuscular disease) or severe malnutrition.

⚙️ What Can Affect Results?

Muscle mass, age, sex, diet (meat, creatine), physical activity, hydration, and certain medications are key factors that may affect creatinine levels.

🔬 Evidence Summary

Moderate evidence: 1 guideline, 2 landmark observational studies.

📚 Most Important Studies on This Topic

1

KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease

Guideline· Kidney International · 2024 · PMID: 38490803

2

New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race

Observational· New England Journal of Medicine · 2021 · PMID: 34554658

3

A New Equation to Estimate Glomerular Filtration Rate

Observational· Annals of Internal Medicine · 2009 · PMID: 19414839

✅ Key Takeaways

💡

What you learned: Creatinine is one of the key indicators of kidney function, but it is influenced by factors such as muscle mass and diet. It provides more meaningful information when evaluated alongside eGFR.

⛔

A single creatinine value cannot diagnose kidney disease. eGFR calculation, clinical context, and additional tests are needed.

🔬 Sources Used on This Page

3 sources · Most recent publication: 2024
📋
Guideline
Expert society and guideline recommendations
1
source
👁
Observational
Observational and cohort studies
2
sources
Overall assessment: Evidence level for this topic is moderate. This page is supported by 1 guideline, 2 observational studies.

📝 Questions to Ask Your Doctor

Be prepared for your appointment. Add questions to your list.

📋 References

[PMID: 38490803] KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International, 2024.
[PMID: 34554658] New Creatinine- and Cystatin C-Based Equations to Estimate GFR without Race. New England Journal of Medicine, 2021.
[PMID: 19414839] A New Equation to Estimate Glomerular Filtration Rate. Annals of Internal Medicine, 2009.
Last reviewed: 4/1/2026
Next review: 4/1/2027

⚖️ Comparisons

Creatinine vs eGFR→

🔗 Related Topics

🩺 Chronic kidney disease🧪 eGFR (tahmini glomerüler filtrasyon hızı)🧪 Üre (BUN)🧪 Açlık kan şekeri (diyabetik nefropati bağlamı)
⚖️ This page does not replace medical advice. Make treatment decisions with your doctor.
Content is based on scientific studies indexed in PubMed and current clinical guidelines.